Roller mill



J. MEZG ER ROLLER MILL Jan. 17, 1933.

Filed July 15, 1931 2 Sheets-Sheet 1 Jaye/2Z0]? j w/ W? J. MEZGER ROLLERMILL Jan. 17; 1933.

Filed July 15, 1951 2 Sheets-Sheet 2 Patented Jan. 17, 1933 UNITED.STATES PATENT OFFICE JACQUES MEZGER, OF ST. GALIi, SWITZERLAND, ASSIGNORTO FIRM GEBR'l'j'D-ER B'UHLER,"

7 OF UZWIL, SWITZERLAND ROLLER MILL Application filed July 15, 1931,Serial No.

This inventionrelates to improvements in roller mills particularly forcereals. The great majority of the roller mills for cereals used areincluded in an automatic sequence of working incidences and thereforerequire to be provided with a device which permits automatic adaptationof the mill to the changing working conditions;

The most frequent changes arise in the feed of stock and are compensatedin the known roller mills by an automatic feeding device, which adaptsitself unattended to the variable feeding conditions. Devices of thiskind are provided for example with automatically adjusting flaps or feedrollers running at variable speeds respectively, while the grindingrolls rotate at all times at the same speed. In this manner the outputof ground goods is necessarily varied inasmuch as with the number ofrevolutions of the grinding rolls remaining constant, and consequentlywith the working surface per unit of time being constant the amount ofround stock er unit of time produced changes and thus according to thequantity of stock admitted to the rolls on a grinding surface of acertain size, in equal time intervals, difierent quantities of groundgoods are obtained. Under these conditions the grinding capacity of themill can not possibly be uniform. Therefore it is desirable to combine aregulating device with the mill which would regulate the amount ofground goods obtained per unit of grinding surface in a given time. 7

This aim is reached according tothe invention in that incontradistinction to all existing mills the number of revolutions of thegrinding rolls is varied in accordance with the feed of stock. I Thisresult can be obtained that in the feed means for the mill a member isinserted which in accordance with the affluent stock actuates aregulating means for adjusting the number of revolutions of the grindingrolls.

In the accompanying drawings several modifications of the regulatingdevice according to the invention are illustrated, by way of exampleonly, in which Fig. l is a sectional side elevation of a 551,033, and inGermany July 23, 1930.

roller mill comprising a mechanically operated regulating means,

Fig. 2 1s a side elevation of a roller mill comprising four rollers,

Fig. 3 is a front elevation of the roller mill shown in Fig. 2, partlyin section, and

Fig. 4; illustrates a detail on a larger scale. In the regulating deviceshown in Fig. 1 a control spring 1 is suspended by a rod 2 from across-bar 3 in the feed chute 4 of the roller to the machine through thechute 4, the portion of which surrounding the spring consists of a glasscylinder in order to make the movements of the spring visible fromoutside the machine andcorrespondingly shifts the linkage comprising thebell crank levers 9 and 10, the connecting rod 11, and the rod 12 onwhich the transmission roller 13 is mounted. The transmission roller 13is inserted between a pair of, driving discs 14:, one, of which beingsecured to the shaft of the roll 6 and the other to the driving pulley15 of the mill. According to the position to which the roller 18 ismoved relatively to the centers of the discs 1% by the expansion orcontraction of the spring 1, the speed of the grinding rolls 6, 7 isdecreased or increased respectively. It is obvious that instead of thefriction disc change speed device 13, 1 1 any other suitable device ofthis kind may be used.

In the Figs. 2 and 3 a roller mill 5 comprising four grinding rolls 16,17, 18, 19 is illustrated wherein the control member is in the form of aresilient plate 20 pivoted at 21 which plate corresponding to thequantity of stock admitted through the respective half of the feed chuteopens or closes the feed gap between the segment 22 and the roller 28more or less, the segment 22 being positively connected to the plate 20by mea-ns'of a knee lever 2%. The rotatable contact arm of a rheostat 25is also connected to the abutment plate 20 by means. of lever arm 26 andlink 27 for regulating the speed of the respective motor 28, throughcable 29. The motors 28 are in driving association with thegrindingrolls 16, 17 and 18, 19 respectively by suitable driving means,for example abelt drive 30 and a spur gear drive 31 so that the speed ofthe motor is increased when the feed of stock increases and conversely.Also with this construction the position of the plate 20 is recognizablefrom the outside of the mill, a pointer 32 being arranged on the pivotof the contact arm of the rheostat 25 indicating said position on thescale 33. By properly gauging the scale 33 it may enable reading off thespecific output of the mill directly.

In place of the abutment plate a spring similar to that shown in Fig. 1may be used as control member also with the arrangement illustrated inFigs. 2 and 3 (see Fig. 4) and vice versa.

Instead of mechanical or electrical auxiliary means operating as aservomotor for actuating the change speed device a hydraulic orpneumatic servomotor may be interposed between the control member andthe change speed device.

The regulating device may be set to work in such manner that thespecific amount of stock admitted to the working rolls is constant orvaried in any suitable relation.

I claim:

1. In a roller mill particularly for cereals, in combination,cooperative grinding rolls, feed means for conveying the stock to saidcooperative rolls, a prime mover operatively associated wtih said rolls,speed regulating means for said prime mover, a control means included insaid feed means and influenced in dependency on the fiow of stock, andtransmission means cooperating with said control means and said speedregulating means for said prime mover, adapting the latter to adjust thespeed of the grinding rolls in accordance with the feed of stock formaintaining the specific output of ground goods from the surface of therolls constant.

2. In a roller mill particularly for cereals, in combination,cooperative grinding rolls, feed means for conveying the stock to saidcooperative rolls, a prime mover operatively associated with said rolls,a change speed gear operatively connected with said grinding rolls, acontrol means included in said feed means and influenced in dependencyon the flow of stock, and a servomotor cooperating with said controlmeans and said change speed gear and adapting the latter to continuouslyadjust the number of revolutions of the grind ing rolls in accordancewith the feed.

3. In a roller mill particularly for cereals,

control means, and connecting means between said control link and saidspeed regulating means for said motor, adapting the latter tocontinuously adjust the number of revolutions of the grinding rolls inaccordance with the feed.

In testimony whereof I have signed my name to this specification.

JACQUES MEZGER.

in combination, cooperative grinding rolls,

feed means for conveying the stock to said cooperative rolls, anelectric motor operatively associated with said cooperative rolls, speedregulating means for said motor, a control means included in said feedmeans and influenced in dependency on the flow of stock, a

control link operatively connected with said

